class Dog():
    def __init__(self,name,age):
        self.name = name
        self.age = age

    def sit(self):
        print(self.name.title() + " is now sitting. ")

    def roll(self):
        print(self.name.title() + " rolled over ")

my_dog = Dog('djy','six')
your_dog = Dog('dxx','seven')

my_dog.sit()
my_dog.roll()